I found a helpful post from TheAutismSite.com about things to say instead of "calm down". I compiled the info into a one-page document which would perfect to keep in your sub folder or somewhere that frequent such as the wall by your desk or on a clipboard that you use. The PDF can be shared with mainstream teachers, parents, etc.
***I simply compiled the info from TheAutismSite.com into a PDF document. I am not affiliated with TheAutismSite.com and I am not a contributor. I am simply a SPED teacher that found this helpful information and want to pass it on to others***
From TheAutismSite.com: “Calm down” is a phrase that all parents are familiar with. It’s a seemingly direct phrase that’s often used to stop children from acting quarrelsome or unruly. So why is it that a child throwing a tantrum doesn’t seem to understand that phrase the same way as adults do? Unfortunately, telling a young child to “calm down” can be tantamount to saying nothing at all. It doesn’t tell children how to appropriately act. They must learn, and a phrase like “calm down” doesn’t teach so much as it tells — in unspecified language, for that matter.
Until kids learn what exactly “calm down” means, it’s not very useful. However, there are other things you can say that make it clearer what you want a child to do. Here are more specific phrases you can use to get your child to “calm down” while also teaching them how to do so.